1. Field of the Invention
The present invention relates to an optical fiber cord, a manufacturing method thereof and manufacturing apparatus thereof and, more particularly, to an optical fiber cord of reduced deterioration of optical loss characteristic originating from residual stress, a manufacturing method thereof and manufacturing apparatus thereof.
2. Description of the Related Art
There is proposed an optical fiber cord provided with an optical fiber core in the center, reinforcing fibers running in parallel thereto and a resin sheath covering them.
The proposed optical fiber cord is produced as follows. One or more reinforcing fibers are disposed around an optical fiber core and the surrounding thereof is covered with thermoplastic resin being heated. These are extruded with an extrusion machine and cooled in a cooling chamber, so that the aforementioned thermoplastic resin is hardened so as to produce a resin sheath. The optical fiber cord is wound up by a winding machine and a production is finished.